Clamping assemblies for securing ligaments to a bone

ABSTRACT

An assembly for securing a plurality of ligaments to a bone includes a first portion exhibited by such as a ring shaped clamp with a tab and slot or a split stem incorporating a plurality of spaced apart ring shaped clamps compressively gripping about the ligaments. A second portion includes at least one of a screw or a ring extending portion engaging a ligament end loop or an undercut recess seating portion extending from an end of a body also incorporating the first portion, and such that the second portion extends from an end of the ligaments and mounts to the bone. The ligaments may further include first and second end-to-end attached sections, between which are configured angled and opposing/aligning incisions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of U.S. Provisional Application61/186,215 filed on Jun. 11, 2009.

FIELD OF THE INVENTION

The present invention teaches various types of clamp or brace assembliesfor repairing ligament damage. More specifically, the present inventiondiscloses a variety of braces, clamps and related devices for repairingeither natural or synthetic ligaments implanted within a reconditionedor replaced joint assembly.

BACKGROUND OF THE INVENTION

The prior art is documented with various assemblies for repairing orinstalling artificial ligaments associated with any of a repaired,reconstructed or artificially installed joint implant. A continualobjective is the ability to properly size and install ligaments forensuring long term use of the reconditioned joint.

As is known, a problem with both (natural) existing joint assemblies andartificial implanted joints is the ability to securely anchor andmaintain the arrangement of ligaments which are necessary for properjoint operation. It is further known that such ligaments can be damagedapart from the associated joint application, thus requiring repair orreplacement. Such artificial ligaments can include such as graphite andcomposite plasticized constructions, these providing the desiredproperties of durability combined with stretch resistance.

SUMMARY OF THE INVENTION

The present invention discloses an assembly for securing a plurality ofligaments to a bone includes a first portion such as a ring shaped clampwith a tab and slot or a split stem incorporating a plurality of spacedapart ring shaped clamps compressively gripping about the ligaments. Asecond portion includes at least one of a screw or a ring extendingportion engaging a ligament end loop or an undercut recess seatingportion extending from an end of a body, such as further including firstand second split portions incorporating the undercut seating portion,and such that the second portion extends from an end of the ligamentsand mounts to the bone.

The ligaments may further include first and second end-to-end attachedsections, between which are configured angled and opposing/aligningincisions. Additional features include the first portion ring shapedclamp further exhibiting an inwardly serrated and ligament grippingsurface. The undercut recess seating portion further can exhibit firstand second trigger displaceable undercut seating portions outwardlydisplaceable from a housing. The trigger seating portions further caninclude a slot defined in a stem portion of the body, a button slidablealong the slot and actuating a linkage connected to the displaceableseating portions.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the attached drawings, when read incombination with the following detailed description, wherein likereference numerals refer to like parts throughout the several views, andin which:

FIG. 1 is an illustration of a clamping assembly for repairing damagedor broken ligaments according to a first embodiment;

FIG. 2 is an illustration of a plurality of ligaments from FIG. 1 and inwhich a “V” notch configuration is imparted between refashioned firstand second sections of strands, this in order to maximize the holdingcapabilities provided by the clamping assembly in FIG. 1;

FIG. 3 is a perspective illustration of the clamping assembly of FIG. 1in both exploded (phantom) and assembled positions;

FIG. 4 is an illustration of a modified clamping assembly incorporatinga plurality of circumferential extending fastening locations;

FIG. 5 is a rotated perspective illustration of the clamping assembly inFIG. 4;

FIG. 6 illustrates an end looped plurality of ligaments mounted to abone by a combination clamp and bone screw according to a furtherembodiment;

FIG. 7 is a side view illustration of the combination clamp and bonescrew of FIG. 8;

FIG. 8 is a perspective illustration of another mounting arrangement forsecuring an end plurality of ligaments to a bone and utilizing a pair ofspaced apart ring clamps, between which a bone screw pierces through afixed section of ligaments to anchor to a bone;

FIG. 9 is a perspective illustration of an end looped plurality ofligaments mounted to a bone by a combination intermediate clamp and endpositioned anchor according to a still further embodiment;

FIG. 10 is an exploded view of the clamp and end anchor of FIG. 9;

FIG. 11 is a perspective illustration of a ligament end mounting clampaccording to a still further configuration and including a bone securingend-anchor integrally formed with an elongated stem for supporting aboutan end of the ligament bunch and which is inwardly compressible by aslidably installed ring clamp;

FIG. 12 is a side view of the installed clap shown in FIG. 11;

FIG. 13 is an exploded perspective of the clamp assembly as depicted inFIGS. 11 and 12 and further illustrating the inwardly serrated surfacesapplied along each of the lengthwise extending and linearlyseparated/compressible halves;

FIG. 14 is a perspective illustration of a ligament end mounting clampsimilar in nature to that disclosed in FIG. 11 and further illustratinga pair of semi-spherical undercut seating portions and associatedtrigger mechanism for outwardly displacing the seating portions from amodified housing associated with the end anchor;

FIG. 15 is an illustration of the ligament end mounting clamp of FIG. 14and further showing the linear displaceable trigger mechanism associatedwith a stem portion of the clamp retracted to withdraw the undercutseating portions inwardly within the housing, such as corresponding toan initial bone installation position of the anchor;

FIG. 16 is a succeeding illustration of the mounting clamp, similar toFIG. 14 and illustrating trigger mechanism displaced to an upper-mostposition corresponding to outward actuation of the seating portions fromthe sleeve shaped and cross wise end extending housing;

FIG. 17 is a somewhat enlarged and corresponding view to that shown inFIG. 14;

FIG. 18 is an illustration of a pair of ring shaped clamps andillustrating inwardly defined serrated teethed patterns for enhancingits gripping properties when installed in compressing fashion overassociated ligaments;

FIG. 19 is an environmental view of the pair of ligament compressingclamps depicted in FIG. 18 and further illustrating the incorporation ofan angled incision defined in the opposing and mating ends of theligament sections according to the further preferred configuration;

FIG. 20 is a perspective view of a ligament end mounting clamp accordingto a yet further variant and including a modified stem configuration forenhancing gripping of a plurality of ligaments of varying thicknesses;

FIG. 21 is rotated perspective view of the clamp of FIG. 20 and furthershowing the first and second spaced apart and integrally formedsemi-circular ring clamp portions with inner knurled surfaces, combinedwith the intermediately positioned, length extending andcircumferentially spaced arms associated with a structural supportingportion of the stem; and

FIG. 22 is a side plan view illustrating the two piece snap-fit natureof the clamp design of FIG. 20 and further showing spaced apart engagingtabs for adjusting a spatial positioning of the first and second piecesrelative to differently sized ligaments.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the several illustrations, the present invention disclosesa variety of clamp and brace assemblies for repairing ligament damage.As previously described, the present invention discloses a variety ofbraces, clamps and related devices for repairing either natural orsynthetic ligaments implanted within a reconditioned or replaced jointassembly.

Additionally, it is understood that ligament repair, reconditioning orreplacement can be associated with implantation of an artificialreplacement joint. In each below described example, the ability tomaintain continuous and non-slipping grip of the ligament strand,combined with the disclosure of effective mechanisms for securelyanchoring the ligaments to a bone location, are stressed. The presentinvention also discloses unique and novel techniques for notching orincising opposing and mating surfaces of first and second individualligament bunches, these subsequently being securely clamped in place bythe various assemblies described herein.

Referring first to FIGS. 1-3, a series of illustrations are provided ofa clamping assembly 10 according to a first non-limiting variant forrepairing damaged or broken ligaments, further depicted as first 12 andsecond 14 end-aligning ligament sections. As best shown in FIG. 2, theend to end aligning and connecting ligament sections (bunches) 12 and 14are illustrated in which a “V” notch separation line configuration isimparted between refashioned and opposing end connections of the first12 and second sections 14 strand sections, this creating an overlapconfiguration between the opposing end portions of the ligament bunchesand in order to maximize the holding capabilities provided by theclamping assembly 10 in FIG. 1.

The incised pattern established between the ligament bunches is shown byfirst end projecting and interconnecting “V” configuring surfaces 16 and18 associated with the upper ligament bunch 12, a corresponding andmating recess pattern being further defined by additional surfaces 20and 22 associated with the second lower bunch 14 and within which isseated the projecting profile of upper ligaments 12. Consistent with thedescription of FIG. 2, it is also understood that the ligament sectionsas described and illustrated herein envision the use of both individual(and larger diameter sized) ligaments or multiple (plural) ligamentbunches, such as described throughout the several views.

As will also be described, the notching or incising of the opposing endsof the ligament sections can be fashioned in varying patterns, thepurpose for which being to achieve maximum restraining and location ofthe sections when gripped between the clamping assembly. It is furtherenvisioned that, in situations where a previously installed ligament isdamaged, such notching and subsequent clamping is desirous in arepairing (in situ) operation where the necessary repairs to the patientcan be achieved without removal or refashioning of the underlying jointassembly.

As again depicted in FIG. 1 and with further reference to FIG. 3 whichillustrates both separated (phantom) and assembled (solid) positions ofthe clamping assembly 10, the clamping assembly can be constructed ofany of a plastic, composite plastic or other hybrid material whichexhibits the necessary properties of bend-ability and durability, andwhich further illustrates the features of first 24 and second 26lengthwise extending and linearly/circumferentially spaced supports. Agenerally ring shaped clamping portion 28 is integrally formed withintermediate locations of the lengthwise supports 24 and 26.

The clamping portion 28 exhibits a generally ring shape and, dependentupon the variant, can include first and second split locations definingseparable halves or (as further depicted) can define a flexible materialwhich is opened at a single location via a first mounting end 30 and asecond circumferentially opposing mounting end 32. The first mountingend 30 exhibits a tab 34 (such as further configuring a ramped or angledportion terminating in an end abutting shoulder 35) and which isengageable within a slot defined within an opposing receiving portion 36(see further inner perimeter surface 37 which establishes the slot)associated with the second mounting end 32. In this fashion, and as isagain shown in FIG. 1, the clamping assembly 10 is capable of beingflexibly applied around the interconnecting interface defined betweenthe ligament bunches 12 and 14, following which the tab 34 is engagedthrough the receiving portion 36.

FIG. 3 further illustrates the clamping assembly 10 in an openedposition (see lengthwise supports 24 and 26 in phantom) prior tolocating and securing about a repaired ligament configuration (bunches12 and 14) such as shown in FIG. 2. In combination with the assembledconfiguration of FIG. 1, FIG. 3 also illustrates the manner in which theelongated supports 24 and 26 are deflected outwardly relative to theinterconnecting ring shaped clamping portion 28 and prior to installingabout the repair location of the end to end disposed ligament sections12 and 14. Also included is the provision of inwardly facing and knurled(or teethed) surface patterns for providing an added measure of grippingof the supports 24 and 26 about the ligament bunches, such as which canbe incorporated into reinforced portions located at opposing and firstand second end locations, see at 38 & 40 and 42 & 44 associated with thesupports 24 and 26, as well as additional knurled portions 46 extendinginwardly in circumferential fashion around the inner perimeter of thering clamp portion 28.

In this fashion, the clamping assembly 10 can be manipulated to encircleand subsequently compress and fixedly engage the repaired ligamentsections 12 and 14 without fear of the ligaments separating prior tothem fusing together. It is also envisioned that the clamp can be sizedto become an enduring part of the ligament repair, in particularinstances, or can be removed in a subsequent operation once the break inthe ligaments has completely healed.

Referring now to FIGS. 4 and 5, an illustration is generally shown at 48a modified clamping assembly incorporating a plurality ofcircumferential extending and generally ring-shaped fastening locationswhich generally corresponds to the assembled version of the clampingassembly 10 in FIG. 3. Specifically, a pair of modified and lengthwisesupports 50 and 52 are structurally maintained by a plurality of spacedapart, integrally formed and generally ring shaped clamping portions 54,56 and 58, each of which generally corresponds in construction to thesingle ring-shaped clamp 28 illustrated in the variant of FIG. 1.

As with the clamp 28, each of the spaced apart clamping portions 54, 56and 58 is integrally formed with upper/lower end and intermediatelocations between the lengthwise supports 50 and 52 and, identical tothat described in FIG. 3 with reference to ring clamping portion 28,each further again includes a first mounting end with a first engagingtab (see as is selected shown by tab 53 for upper clamping portion 54)which is received within a slot defined within an opposing receivingportion (further exemplary shown by slot 55 and receiving portion 57)associated with a second mounting end. Also again shown are respectivepluralities of inner perimeter surface applied knurled or teethedsurface patterns (see as shown by example at 59 for upper clampingportion 54 and which is identical to that previously illustrated at 46in FIG. 3), which are also identical to that identified and described inthe embodiment of FIG. 3 and which facilitate compressive gripping andpermanent location about the repaired ligament sections 12 and 14 alsodepicted in FIG. 4.

Referring now to FIGS. 6 and 7, both perspective and side plan views areshown of an end looped plurality of ligaments, at 60, mounted to a bone(not shown) by a combination clamp 62 and bone screw 64 according to afurther embodiment. As described previously, the ligaments 60 can beeither natural or man-made and, upon being fashioned in the end-loopedfashion illustrated, are fixed by application of the clamp 62.

As further shown, the clamp 62 can exhibit a tapered or non-linear threedimensional shape to accommodate the folded over ligament end-loop andcan be constructed of a plastic or other suitable material and includesa split location 66 such as permitting the clamp to be forciblymanipulated in position around the looped end of the ligaments,following which they are snap-fit or tightened such that inner facingknurled patterns (see at 68 as is also shown in FIG. 10) engage andinwardly compress the overlapping ligament bunches. The screw 64 ispre-positioned during the initial folding of the ligament ends and isfixedly maintained about the inner looped end following installation ofthe clamp 62. As further shown in FIG. 7, the shaft portion of the screw64 can exhibit varying thread profiles, see as shown at 70 and 72, thispromoting gripping forces when installed within the user's bone (see asfurther shown in phantom at 74)

FIG. 8 illustrates a perspective view of a further mounting arrangementfor securing an end plurality of ligaments, shown at 76, to a bone (notshown) and which utilizes a pair of spaced apart ring clamps 78 and 80,between which a modified version of the bone screw 64 pierces through afixed section of ligaments and in order to anchor to a specifiedlocation of the bone. The ring clamps 78 and 80 each exhibit a splitconfiguration allowing the clamps to separate into halves duringassembly around the ligaments.

Inner circumferentially extending surfaces of the clamps each furtherexhibit inwardly facing and accordion-like serrated patterns, see inphantom at 82 and 84 respectively, which assist in providing thenecessary compressive gripping engagement about the plural ligamentstrands. Although not clearly shown, it is understood that the ringclamps 78 and 80 can each further consist of assembled split portions,such as further utilizing any type of snap-fit or adjustable features toensure secure and fixed location with respect to the ligaments.

The modified anchor screw 64 can again be constructed of a plastic orcomposite material and is typically pre-positioned in piercing fashionthrough the ligament strands before installation of the split rings 78and 80. In combination with the varying thread patterns 70 and 72previously described (see FIG. 7), a further plurality of increaseddiameter and narrower thickness threads are shown at 86 associated withthe screw 64 and function to provide enhanced gripping of the ligaments76, this preventing the screw 64 from inadvertently detaching from theligaments during subsequent use and progressive fusing of the ligamentsto the bone surfaces, and which is ensured by the clamping forcesasserted by the adjoining ring clamps 78 and 80.

FIGS. 9 and 10 illustrate a pair of environmental and separateperspective views, respectively of an end looped plurality of ligaments(again at 60 in FIG. 9 and referring to the previously describedembodiment of FIG. 6) and which is mounted to a bone by a combinationintermediate clamp (see again at 62 and according to that previouslydescribed in FIG. 6) as well as an end positioned anchor 88. The anchor88 can be constructed of a plasticized or composite plastic materialwhich replaces the bone screw 64 associated with the previous embodimentand also includes a first aperture defined end, see lower ring 90, forreceiving the looped ligament strands 60 prior to the same be fastenedto the (split ring assemble or solid one piece) clamp 62. An upper endof the anchor 88 includes a generally dual-end bulbous shaped portion92, this corresponding to a recessed undercut pattern (not shown in thisvariant) associated with a machining process applied to an associatedbone (also not shown) and to which is permanently secured the projectingportion 92 of the anchor 88.

Referring now to FIGS. 11, 12 and 13, a series of illustrations areshown in perspective environmental, side assembled and perspectiveexploded respectively of a ligament end mounting clamp, generally at 94,according to a still further configuration. The clamp 94 includes a bonesecuring undercut end-anchor assembly in the form of a projectingportion 96 (which is similar to the projection portion 92 in FIG. 10),and which is integrally formed with an elongated stem for supportingabout an end of a ligament bunch 98 and which is inwardly compressibleby a slidably installed ring clamp 100.

The exploded view of FIG. 13 best illustrates the configuration of theanchor assembly 94 and, in addition to the undercut engaging end 96,further shows an integrally extending stem consisting of first andsecond sections 102 and 104 (both extending from a common trunk 105located in communication with an underside of the projecting portion96), the individually branching sections 102 and 104 further separatedby a pair of linear extending slots 106 and 108. As further shown, aninner profile of each of the stem sections 102 and 104 further exhibit aserrated pattern (at 110 and 112 in FIG. 13) which enable the clampassembly to be pre-positioned over the extending end of the ligamentbunch 98 as shown in FIG. 11.

At this point, the ring clamp 100, which exhibits a generally annularshape, is installed in a progressive sliding fashion over end-most (andslightly projecting) and generally semi-cylindrical shaped portions 114and 116 associated with the stem sections 102 and 104, following whichthe ring clamp 100 seats within intermediate recessed surfaces 118 and120 separating the end-most portions 114 and 116 with upper locatedportions of the stem sections 102 and 104. The dimensions of therecessed profile (see again FIG. 13) defined in the intermediatelocation of the clamp stem are such that the slidably engaged ring clamp100 is fixedly seated in place (FIGS. 11 and 12) while exerting asufficient compressive holding and gripping forces against the ligamentbunch 98.

Additional features not specifically shown include the collar beingheight adjustable along the inwardly compressible stem in order tomodify a clamping compressive force exerted on the ligament bunch. Alsoshown at 122 is an upper end aperture associated with the undercutengaging top end 96 through which projects a very end point of theligament bunch, see further at 124 in FIGS. 11 and 12, and in order topromote ligament fusion to the interior profile of the bone (not shown)within which the undercut portion 96 is anchored.

FIGS. 14-17 disclose a series of perspective illustrations of a ligamentend mounting clamp, generally at 94, according to a still furtherconfiguration similar to that previously described in FIGS. 11-13, butin which the fixed upper end mounted undercut anchor (at 96 in FIG. 11)has been reconfigured by the addition of a pair of semi-sphericalundercut seating portions 126 and 128 and associated trigger mechanismfor outwardly displacing the seating portions 126 and 128 from amodified housing 130 similar to a “T” connector like fitting associatedwith the end anchor. The trigger mechanism is initially identified byslot 132 positioned along a lengthened upper trunk end 133 of theinterconnecting stem portion (see again lower communicating split stemsections 102 and 104) through which the ligament bunch 98 extends.

An actuating mechanism is incorporated into an upper end of the clamphousing and is connected to a button 134 (see triangular shapedactuating mechanism 135 in phantom in FIG. 16) seated within the slot132 and which is actuated via a stem or rod 133 interconnecting thewedge 135 with the button 134 to travel upwardly along the length of theslot 132 concurrent with selectively upwardly/outwardly actuating ordownwardly/inwardly retracting individual undercut seating portions 126and 128. The initial retracted position of undercut seating portions 126and 128 within the upper end housing 130 in FIG. 15 corresponds to aninitial bone installation position of the anchor within a previouslyundercut location (see at 136 in FIG. 14 and which is communicated to anexterior of the bone via a narrowed neck 138), such undercut formationbeing known through the implementation and manipulation of appropriatemedical drilling and routing tools.

The length and width dimensions of the sleeve shaped housing 130 (withinwardly retracted seating portions 126 and 128) is understood to besufficient to permit insertion through the narrowed neck profile 138 ofthe bone. The trigger mechanism is subsequently engaged (by moving thebutton 134 upwardly along the slot 132) in order to cause the internalactuating mechanism, such as again the wedge type component 135 andwhich can also include a cam or bevel arrangement of some type, tooutwardly displace the seating portions 126 and 128 from inside thehousing 130 to the position shown in FIG. 14 and in order to permanentlyseat and anchor the anchor assembly within the undercut configuration ofthe bone. It is also envisioned that the triangular/wedge shaped element135 can also exhibit an inner aperture (see perimeter defining innerwall 137) which permits the ligament bunch 124 to be pre-located throughthe interior of the wedge in the manner shown and so that the triangularwedge can be actuated without interfering with the positioning of theligaments.

In a possible alternate arrangement to the wedge shaped component 135depicted in FIG. 16, another possible example of a laterally displacingmechanism is representatively illustrated in FIG. 15 (which illustratesthe anchor assembly without the ligament bunch 98) and in which arepartially evident inner/opposing engaging locations 140 and 142associated with the laterally displaceable seating portions 126 and 128.The seating portions 126 and 128 are biased outwardly by an alternatelyconfigured cam or other type displacing portion (this being furtherrepresentatively shown in selected view of FIG. 17 as including a gearrack 141 which is mechanically linked at a lower end to the triggerbutton 134 and which, upon traveling upwardly, rotates a gear 143. Thegear 143 in turn mounts and coactively rotates a pair of oppositelyextending and exteriorly threaded shafts 145 which are seated withininternally threaded pockets defined in the base of each seatingprojection 126 and 128 and, upon actuating, causes the portions 126 and128 to oppositely and outwardly separate.

As previously described with reference to the embodiment of FIGS. 11-13,the gear actuating mechanism 143 and 145 can also be reconfigureddifferently than shown in FIG. 17 (such as by repositioning the rotatinggear 143 and oppositely extending threaded drive shafts 145) in such afashion that the ligament bunch 124 can remain permanently affixed tothe anchor assembly. Further, and via the split stem arrangement withinwardly teethed and serrated surfaces combined with the provision ofthe ring clamp 100 which forcibly engages over the lower end portions114 and 116 associated with the split stem 102 and 104, subsequentlyseats within the reduced intermediate recessed surfaces 118 and 120,separating the end-most portions 114 and 116 with upper located portionsof the stem sections 102 and 104, this again in order to maintain apermanent gripping arrangement with the ligament bunch 98. As alsopreviously described, the upper projecting ends 124 of the ligamentbunch 98, being in contact with the inner undercut surface of the bone,also promote additional adhering growth to the associated bone.

FIGS. 18 and 19 disclose a pair of exploded and environmental assembledperspective views of another version ligament clamp assembly and inwhich a pair of ring-shaped and spaced apart clamps 146 and 148 areconfigured for gripping and compressing individual linear locationsassociated with first 151 and second 153 sections of ligaments locatedproximate to a damaged area. FIG. 18 is an enlarged view better showingthe configuration of the pair of ligament compressing clamps 146 and148, each of which are fairly identically constructed to the ring shapedclamp previously identified at 28 integrally incorporated into theoverall clamping assembly referenced in the embodiment 10 of FIG. 1. Inparticular, each of the clamps 146 and 148 likewise include a firstmounting end exhibiting a tab 150 and 152 (such as again furtherconfiguring a ramped or angled portion terminating in an end abuttingshoulder) which is engageable within a slot 154 and 156 defined withinan opposing receiving portion associated with the second mounting end.

Also illustrated is the incorporation of an angled incision, at 158,defined in the opposing and mating ends of the end to end abuttingligament sections 151 and 153 according to the further preferredconfiguration. As with the “V” notch configuration previously described,at 16-22 in FIG. 2, the 45° angled cut 158 referenced in FIG. 19provides another non-limiting example of an increased surface splicingoperation for creating a maximum area of inter-ligament growth oradhesion, such as during a healing process following initialreconditioning of the ligaments and application of the clamps (such asin situ within the patient).

The pair of ring shaped clamps in FIG. 18 again illustrate inwardlydefined serrated teethed patterns, at 160 and 162, for enhancing itsgripping properties when installed in compressing fashion over theligament bunches 151 and 153. Upon installation, the projecting tabs 150and 152 each include a progressing ramp (see at 163 for selected tab152) terminating in an inner seating shoulder 164. The tab 150 is causedto deflect inwardly, see arrow 165, during passage therethrough of theramp 163, and which is dimensioned to pass through the slot 154.Following this, an interconnected and narrowed neck 166 communicateswithin the slot 154 and whereby the resilient properties of the tab 150bias it outwardly in the direction of arrow 168 to lock the clamp inplace.

Referring finally to FIGS. 20-22 a related version of a ligament endanchor undercut clamp assembly, as generally shown at 170, is configuredsimilar to that illustrated at 94 in FIG. 11, with the exception thatthe entire anchor (head) and stem portions are constructed as first 172and second 174 split portions which are bounded by a central and lengthextending parting line 175. Also shown is a modified stem configurationwhich provides enhancing gripping of the plurality of ligaments 98, suchas being of varying thicknesses.

FIG. 21 is a rotated (underside facing) perspective view of the clamp ofFIG. 20 and further shows the provision of first 176 and second 178spaced apart and integrally formed semi-circular ring clamp portions,these further exhibiting inner knurled surfaces 180 and 182. Combinedwith intermediately positioned, length extending and circumferentiallyspaced arms 184 and 186 interconnecting an upper end of the stem withthe bottom located ring clamp portions 176 and 178, the structuralsupporting stem provides both enhanced gripping of the end location ofthe ligament bunch 98 (such as further enhanced by the provision of theinwardly facing and knurled/serrated surfaces).

FIG. 22 is a side plan view illustrating the two piece snap-fit natureof the clamp design of FIG. 20 and further showing the feature of spacedapart engaging tabs, at 188, 190 and 192, located at respective head,stem and bottom ring clamp locations of selected split portion 174. Inthis fashion, the tabs 188, 190 and 192 biasingly engage matinglocations associated with the other split portion 172 for adjusting aspatial positioning of the first and second split portion piecesrelative to one another, such as in order to accommodate differentlysized ligament bunches.

Having described my invention, other and additional preferredembodiments will become apparent to those skilled in the art to which itpertains, and without deviating from the scope of the appended claims.

I claim:
 1. An assembly for securing a plurality of ligaments to a bone,comprising: a one piece body including a stem terminating in an endsituated and crosswise accessible sleeve shaped housing exhibiting anopen circular profile; a pair of semispherical shaped seating portionssupported in opposite facing directions within said sleeve shapedhousing in a first retracted position, said stem and housingcollectively defining a linear extending interior adapted for receivingthe plurality of ligaments arranged in an extending bunch andcompressively gripping the ligaments; a trigger mechanism incorporatedinto said body and laterally outwardly displacing said seating portionsfrom within said sleeve shaped housing into a second expanded andengagement position within a previously undercut location defined withinthe bone and upon pre-inserting said sleeve shaped housing into analigning position with the undercut location, said body and ligamentbunch adapted to being anchored to the bone; said trigger mechanismfurther including a slot extending along a lengthened upper trunk end ofsaid stem, a button projecting from said slot and, upon being translatedupwardly, actuating a linkage for laterally outwardly displacing saidseating portions; and said linkage further including a gear rackmechanically linked to at a lower end to said button, upon beingupwardly actuated, said button engages a rotatably supported gear,rotation of said gear coactively rotating a pair of threaded shaftssupported within said sleeve shaped housing, with opposite extendingends of said shafts threadably inter-engaging within internal threadedpockets defined in a base of each seating portion and driving laterallyoutward displacement of said seating portions.
 2. The assembly asdescribed in claim 1, said linkage further comprising a wedge shapedcomponent supported in linearly displaceable fashion within said housingand contacting opposing inner surfaces of said outwardly displaceableseating portions.
 3. The assembly as described in claim 1, furthercomprising a ring clamp supported in linearly displaceable fashion overa base location of said stem in which are defined a pair of linearextending slots, displacement of said clamp compressingcircumferentially spaced portions of said stem in order to grip theligament bunch.